System and method for charging or powering devices, including mobile devices, machines or equipment

ABSTRACT

In accordance with various embodiments, described herein are systems and methods for enabling efficient wireless power transfer and charging of devices and/or batteries, including in some embodiments freedom of placement of the devices and/or batteries in one or multiple (e.g. one, two or three) dimensions, and/or improved features such as ease of use and compatibility. Exemplary applications include beam inductive or magnetic charging and power for use in, e.g., mobile, electronic, electric, lighting or other devices, machines, batteries, power tools, kitchen, military, medical, industrial tools or systems, robots, trains, buses, trucks and/or vehicles, and other environments.

CLAIM OF PRIORITY

This is a continuation of U.S. patent application titled “SYSTEM ANDMETHOD FOR CHARGING OR POWERING DEVICES, SUCH AS MOBILE DEVICES,MACHINES OR EQUIPMENT,” application Ser. No. 15/650,921, filed Jul. 16,2017, which is a continuation-in-part application claims the benefit ofpriority to U.S. patent application titled “SYSTEM AND METHOD FORCHARGING OR POWERING DEVICES, SUCH AS ROBOTS, ELECTRIC VEHICLES, OROTHER MOBILE DEVICES OR EQUIPMENT,” application Ser. No. 13/829,786,filed Mar. 14, 2013, which in turn claims priority to U.S. Provisionalpatent application titled “SYSTEM AND METHOD FOR CHARGING OR POWERINGDEVICES, SUCH AS ROBOTS, ELECTRIC VEHICLES, OR OTHER MOBILE DEVICES OREQUIPMENT,” Application No. 61/725,607, filed Nov. 13, 2012, thedisclosures of which are incorporated by reference.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. Patent Publication No. 20120235636(U.S. patent application Ser. No. 13/352,096) titled “SYSTEMS ANDMETHODS FOR PROVIDING POSITIONING FREEDOM, AND SUPPORT OF DIFFERENTVOLTAGES, PROTOCOLS, AND POWER LEVELS IN A WIRELESS POWER SYSTEM”, filedJan. 17, 2012, which claims the benefit of priority to U.S. ProvisionalPatent Application No. 61/433,883, titled “SYSTEM AND METHOD FORMODULATING THE PHASE AND AMPLITUDE OF AN ELECTROMAGNETIC WAVE INMULTIPLE DIMENSIONS”, filed Jan. 18, 2011; U.S. Provisional PatentApplication No. 61/478,020, titled “SYSTEM AND METHOD FOR MODULATING THEPHASE AND AMPLITUDE OF AN ELECTROMAGNETIC WAVE IN MULTIPLE DIMENSIONS”,filed Apr. 21, 2011; and U.S. Provisional Patent Application No.61/546,316, titled “SYSTEMS AND METHODS FOR PROVIDING POSITIONINGFREEDOM, AND SUPPORT OF DIFFERENT VOLTAGES, PROTOCOLS, AND POWER LEVELSIN A WIRELESS POWER SYSTEM”, filed Oct. 12, 2011; and is also related toU.S. patent application Ser. No. 13/828,789, titled “SYSTEMS AND METHODSFOR WIRELESS POWER TRANSFER”, Attorney Docket No. AFPA-01035US1, filedMar. 14, 2013, which claims the benefit of priority to U.S. Provisionalpatent application titled “SYSTEMS AND METHODS FOR PROVIDING POSITIONINGFREEDOM IN THREE DIMENSIONS FOR WIRELESS POWER TRANSFER”, ApplicationNo. 61/613,792, filed Mar. 21, 2012; each of which above applicationsare herein incorporated by reference.

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in the Patent and TrademarkOffice patent file or records, but otherwise reserves all copyrightrights whatsoever.

FIELD OF INVENTION

Embodiments of the invention are generally related to systems andmethods for enabling wireless charging or power supply to one or manyreceivers placed on or near a wireless charger or power supply.

BACKGROUND

Wireless technologies for powering and charging mobile and otherelectronic or electric devices, batteries and vehicles have beendeveloped. Such systems generally use a wireless power charger ortransmitter, and a wireless power receiver in combination, to provide ameans for transfer of power. In some systems, the charger and receivercoil parts of the system are aligned and of comparable or similar size.However, such operation typically requires the user to place the deviceor battery to be charged in a specific location with respect to thecharger. These are the general areas that embodiments of the inventionare intended to address.

SUMMARY

Wireless technologies for powering and charging mobile electric orelectronic device or system, such as a robot, electric vehicle (EV),bus, train, or other system or battery generally use a wireless powercharger or transmitter, and a wireless power receiver in combination, toprovide a means for transfer of power across a distance.

For safe and efficient operation of basic wireless charging systems, thecharger or transmitter and receiver coils of the system are typicallyaligned and of comparable or similar size. Such operation typicallyrequires the user to place the device, vehicle or battery to be charged(and hence its receiver) in a specific location with respect to thecharger.

In accordance with an embodiment, to enable ease of use, it is desirablethat the receiver can be placed on a larger surface area charger,without the need for specific alignment of the position of the receiver.It may also be desirable to be able to charge or power multiple devicesof similar or different power and voltage requirements, or operatingwith different wireless charging protocols, on or near the same chargingsurface; or to provide some degree of freedom with respect to verticaldistance (i.e., away from the surface of the charger) between thecharger and the receivers.

An example usage of such a large distance or gap is in charging ofdevices or systems such as electric vehicles (EV) or buses, electricbicycles or motorcycles, robots, other mobile vehicles and trains. Otherexamples or use cases include where the charger may need to bephysically separated from the device or battery to be charged, such aswhen a charger is incorporated beneath a surface such as the centerconsole of a car or under the surface of a table or desk, etc.

In accordance with various embodiments, described herein are systems andmethods for enabling efficient wireless power transfer and charging ofdevices and/or batteries, including in some embodiments freedom ofplacement of the devices and/or batteries in one or multiple (e.g., one,two or three) dimensions, and/or improved features such as ease of useand compatibility. Exemplary applications include inductive or magneticcharging and power for use in, e.g., mobile, electronic, electric,lighting or other devices, batteries, power tools, kitchen, military,medical, industrial tools or systems, robots, trains, buses, electricbicycles or motorcycles, personal mobility (e.g., Segway) devices,trucks and/or vehicles, and other systems or environments.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates a wireless charger or power system comprises a firstcharger or transmitter part and a second receiver part, in accordancewith an embodiment.

FIG. 2 illustrates a wireless power transfer system in accordance withan embodiment.

FIG. 3 illustrates a system for wireless charging of electric vehicles,in accordance with an embodiment.

FIG. 4 illustrates an AC magnetic flux generated by a wireless powercharger coil, in accordance with an embodiment.

FIG. 5 illustrates the use of magnetic layers that extend beyond thecharger and receiver coil areas, in accordance with an embodiment.

FIG. 6 illustrates a crossed charger and receiver coil and shieldgeometry, in accordance with an embodiment.

FIG. 7 illustrates permeability of Ferromagnetic materials, inaccordance with an embodiment.

FIG. 8 illustrates a hysteresis curve for a hard ferromagnetic materialsuch as steel, in accordance with an embodiment.

FIG. 9 illustrates real and imaginary parts of the permeability of aferromagnetic material as a function of applied electromagneticfrequency, in accordance with an embodiment.

FIG. 10 illustrates magnetization curves of a high permeabilityproprietary soft magnetic ferrite material, in accordance with anembodiment.

FIG. 11 illustrates a flux guided and magnetic coupling system includinga magnetic switching layer, in accordance with an embodiment.

FIG. 12 illustrates a high level block diagram of a wireless powertransfer system, in accordance with an embodiment.

FIG. 13 illustrates use of one or more chargers and/or coils that covera length of road, path or train track, in accordance with an embodiment.

DETAILED DESCRIPTION

With the proliferation of electrical and electronic devices and vehicles(which are considered examples of devices herein), means of providingsimple and universal methods of providing power and or charging of thesedevices are becoming increasingly important.

In accordance with an embodiment, the term device, system, product, orbattery is used herein to include any electrical, electronic, mobile,lighting, or other product, batteries, power tools, cleaning,industrial, kitchen, lighting, military, medical, dental or specializedproducts, trains, vehicles, or movable machines such as robots or mobilemachines, whereby the product, part, or component is powered byelectricity or an internal or external battery and/or can be powered orcharged externally or internally by a generator or solar cell, fuelcell, hand or other mechanical crank or alike. In accordance with anembodiment, a device, system, product, or battery can also include anattachable or integral skin, case, component, battery door or attachableor add-on or dongle type of receiver component to enable the user topower or charge the product or device.

Induction is the generation of electromotive force (EMF) or voltageacross a closed electrical path in response to a changing magnetic fluxthrough any surface bounded by that path. Magnetic resonance is arelatively newer term that has been used recently to describe inductivepower transfer where the charger and receiver may be far apart or usingdissimilar coil sizes or shapes. Since this is in general a form ofinduction, in the remainder of this document the term induction is used,but the terms induction and magnetic resonance are sometimes usedinterchangeably herein to indicate that the method of power transfer maybe in either domain or a combination thereof.

In accordance with various embodiments, an inductive power transmitteremploys a magnetic induction coil(s) transmitting energy to a receivingcoil(s) in a device or product, case, battery door, or attachable oradd-on component including attachments such as a dongle or a batteryinside or outside of device or attached to device through a connectorand/or a wire, or stand-alone part placed near the power transmitterplatform. The receiver can be an otherwise incomplete device thatreceives power wirelessly and is intended for installation or attachmentin or on the final product, battery or device to be powered or charged,or the receiver can be a complete device intended for connection to adevice, product or battery directly by a wire or wirelessly. Inaddition, the mobile device, system or battery can be stationary ormoving during receipt of charge or power.

In accordance with an embodiment, as used herein, the terms wirelesspower, charger, transmitter or inductive or magnetic resonance power andcharger are used interchangeably. In accordance with an embodiment, thewireless charger can be a flat or curved surface or part that canprovide energy wirelessly to a receiver. It can also be constructed offlexible materials and/or coils, or even plastic electronics to enablemechanical flexibility and bending or folding to save space or forconformity to non-flat surfaces. The wireless charger can be directlypowered by an AC power input, DC power, or other power source, such as acar, motorcycle, truck or other vehicle or airplane or boat or shippower outlet, or vehicle, boat, ship or airplane itself, primary(non-rechargeable), or rechargeable battery, solar cell, fuel cell,mechanical (hand crank, wind, water source, etc.), nuclear source orother or another wireless charger or power supply or a combinationthereof. In addition, the wireless charger can be powered by a part suchas a rechargeable battery which is itself in turn recharged by anothersource such as an AC or DC power source, vehicle, boat or ship orairplane outlet or vehicle, boat or ship or airplane itself, solar cell,fuel cell, or mechanical (hand crank, wind, water, etc.) or nuclearsource, etc. or a combination thereof. In addition, in cases where thewireless charger is powered by a rechargeable source such as a battery,the battery can also be itself in turn inductively charged by anotherwireless charger. The wireless charger can be a stand-alone part,device, or product, or can be incorporated into another electric orelectronics device or vehicle or airplane or marine vehicle or boat. Thewireless charger may also have other functions built in or beconstructed such that it is modular and additionalcapabilities/functions can be added as needed.

In accordance with an embodiment, the product or device to be chargeddoes not necessarily have to be portable and/or contain a battery totake advantage of induction or wireless power transfer. For example, alighting fixture or an industrial tool or system that is typicallypowered by an AC outlet or a DC power supply can be placed on or near awireless charger and receive power wirelessly. The wireless receiver canbe a flat or curved surface or part that can receive energy wirelesslyfrom a charger. The receiver and/or the charger can also be constructedof flexible materials and/or coils or even plastic electronics to enablemechanical flexibility and bending or folding to save space or forconformity to non-flat surfaces.

In accordance with various embodiments, devices may contain internalbatteries, and the device may or may not be operating during receipt ofpower. Depending on the degree of charge status of the battery or itspresence and the system design, the applied power may provide power tothe device, charge its battery or a combination of the above. The termscharging and/or power are used interchangeably herein to indicate thatthe received power can be used for either of these cases or acombination thereof. In accordance with various embodiments the termscharger, power supply and transmitter are also used interchangeably.

As shown in FIG. 1, in accordance with an embodiment 100, a wirelesscharger or power system comprises a first charger or transmitter part,and a second receiver part. The charger or transmitter can generate arepetitive power signal pattern (such as a sinusoid or square wave from10's of Hz to several MHz or even higher, but typically in the 100 kHzto several MHz range) with its coil drive circuit and a coil or antennafor transmission of the power. The power section may comprise one ormore switches driven with appropriate pattern by a controller. As anexample, a half-bridge driver is shown. However, any other appropriategeometry such as resonant converter, resonant, full bridge, half bridge,E-class, zero voltage or current switching, flyback, or any otherappropriate power supply topology can be used.

In accordance with an embodiment, the charger or transmitter alsoincludes a communication and regulation/control system that detects areceiver and/or turns the applied power on or off and/or modify theamount of applied power by mechanisms such as changing the amplitude,frequency or duty cycle, etc., or by a change in the resonant conditionby varying the impedance (capacitance or inductance) of the charger or acombination thereof of the applied power signal to the coil or antenna.In accordance with an embodiment, the charger can also be the whole orpart of the electronics, coil, shield, or other part of the systemrequired for transmitting power wirelessly. The electronics may comprisediscrete components or microelectronics that when used together providethe wireless charger functionality, or comprise an Application SpecificIntegrated Circuit (ASIC) chip, a multi-chip module (MCM) or chipsetthat is specifically designed to function as the whole or a substantialpart of the electronics for wireless charger system.

In accordance with an embodiment, the second part of the system is areceiver that includes a coil or antenna to receive power, a method forchange of the received AC voltage to DC voltage, such as rectificationand smoothing with one or more rectifiers or a bridge or synchronousrectifier, etc. and one or more capacitors. In instances where thevoltage at the load does not need to be kept within a tight tolerance orcan vary regardless of the load resistance or the resistance of the loadis always constant, the rectified and smoothed output of the receivercan be directly connected to a load. Examples of this scenario mayinclude lighting applications, or applications where the load is aconstant resistance such as a heater or resistor, etc. In theseinstances, the receiver system could be made simple and inexpensive. Inother instances, the resistance or impedance of the load changes duringoperation. This includes instances where the receiver is connected to adevice whose power needs may change during operation or when thereceiver is used to charge a battery. In these instances, the outputvoltage may need to be regulated so that it stays within a range ortolerance during the variety of operating conditions. In theseinstances, the receiver may optionally include a regulator such aslinear, buck, boost or buck boost, etc. regulator and/or switch for theoutput power. Additionally, the receiver may include a method for thereceiver to communicate with the charger.

In accordance with an embodiment, the receiver may optionally include areactive component (inductor or capacitor) to increase the resonance ofthe system and a switch to allow switching between a wired and wirelessmethod of charging or powering the product or battery. The receiver mayalso include optional additional features such as including Near FieldCommunication, Bluetooth, WiFi, RFID or other communication and/orverification technology.

In accordance with an embodiment, the charger or transmitter coil andthe receiver coil can have any shape desired and can be constructed ofPCB, wire, Litz wire, metal tubing or a combination thereof. To reduceresistance, the coils can be constructed of multiple tracks or wires inthe PCB and/or wire construction or a combination thereof. For PCBconstruction, the multiple layers can be in different sides of a PCBand/or different layers and layered/designed appropriately to provideoptimum field pattern, uniformity, inductance, and/or resistance orQuality factor (Q) for the coil. Various materials can be used for thecoil conductor such as different metals and/or magnetic material orplastic conductors, etc. Typically, copper with low resistivity can beused. The design should also take into account the skin effect of thematerial used at the frequency of operation to preferably provide lowresistance.

In accordance with an embodiment, the charger and/or the receivers canincorporate magnetic materials (or a material with permeability that isdifferent than that of air or value of 1) with the coils to provideshielding and/or guiding of flux or magnetic flux switching. Thesemagnetic layers may have different properties depending on theirintended purpose and in accordance with an embodiment, one or several ofthem can be incorporated into the charger and/or receiver to accomplishdifferent goals. In accordance with various embodiments, the magneticmaterials, layers or structures used in the charger and or receivers areherein referred to as magnetics of the system.

In accordance with an embodiment, the receiver can be an integral partof a device or battery as described above, or can be an otherwiseincomplete device that receives power wirelessly and is intended forinstallation or attachment in or on the final product, battery or deviceto be powered or charged, or the receiver can be a complete deviceintended for connection to a device, product or battery directly by awire or wirelessly. Examples include replaceable covers, skins, cases,doors, jackets, surfaces, etc or attachable components or systems fordevices, vehicles or batteries that can incorporate the receiver or partof the receiver and the received power can be directed to the device orvehicle through connectors in or on the device or battery or the normalwired connector (or power jack) of the device or battery.

In accordance with an embodiment, the receiver may also be a part ordevice similar to a dongle or cable that can receive power on or nearthe vicinity of a charger and direct the power to a device, vehicle,system or battery to be charged or powered through a wire and/orappropriate connector. Such a receiver may also have a form factor thatallows it to be attached in an inconspicuous manner to the device orvehicle such as a part that is attached to the outer surface at thebottom, front, side, or back side of a system, vehicle, robot, etc orother electronic device and route the received power to the inputpower/charger connector or jack of the device. The connector of such areceiver can be designed such that it has a pass through or a separateconnector integrated into it so that a wire cable for providing wiredcharging/power or communication can be connected to the connectorwithout removal of the connector thus allowing the receiver and itsconnector to be permanently or semi-permanently be attached to thedevice throughout its operation and use. Many other variations of thereceiver implementation are possible and these examples are not meant tobe exhaustive.

In accordance with an embodiment, the receiver can also be the whole orpart of the electronics, coil, shield, or other part of the systemrequired for receiving power wirelessly. The electronics may comprisediscrete components or microcontrollers that when used together providethe wireless receiver functionality, or comprise an Application SpecificIntegrated Circuit (ASIC) chip or chipset that is specifically designedto function as the whole or a substantial part of the electronics forwireless receiver system.

Optional methods of communication between the charger and receiver canbe provided through the same coils as used for transfer of power,through a separate coil, through an RF or optical link, through RFID,Bluetooth, WiFi, Wireless USB, NFC, Felica, Zigbee, Wireless Gigabit(WiGig), etc. or through such protocols as defined by the Wireless PowerConsortium (WPC), Alliance for Wireless Power (A4WP) or other protocolsor standards, developed for wireless power, or other communicationprotocol specific to a particular application, such as Dedicated ShortRange Communications (DSRC) used in vehicle communication, orcombination thereof.

While a system for communication between the charger and receiverthrough the power transfer coil or antenna is described above, inaccordance with an embodiment the communication can also be implementedthrough a separate coil, a radio frequency link (am or fm or othercommunication method), an optical communication system or a combinationof the above. The communication in any of these methods can also bebi-directional rather than uni-directional as described above.

As an example, FIG. 2 shows a system 120 in accordance with anembodiment, wherein a dedicated RF channel for uni-directional orbi-directional communication between the charger and receiver isimplemented for validation and/or regulation purposes. This system issimilar to the system shown in FIG. 1, except rather than loadmodulation being the method of communication, the MCU in the receivertransmits necessary information over an RF communication path. This RFchannel can be any appropriate protocol such as WiFi, wireless Zigbee,Bluetooth, RFID, NFC, or automotive specific protocols such as DedicatedShort Range Communications (DSRC) or any protocol specifically definedfor wireless power. A similar system with LED or laser transceivers ordetectors and light sources can be implemented. Advantages of such asystem include that the power received is not modulated and thereforenot wasted during communication and/or that no electronic noise due tothe modulation is added to the system.

Some implementations of wireless charging for electric vehicles (EVs)use circular transmitter and receiver coils operating in resonance totransfer power between them. An example of such system 130 is shown inFIG. 3. In such systems, the AC magnetic flux (shown 140 in FIG. 4)generated by the charger is mostly vertically oriented and creates acorresponding AC current in the receiver coil to transfer power. Inaddition, these wireless charging systems typically include magneticfield shielding behind the charger and/or receiver coils. It isparticularly important to shield the vehicle and surrounding areas fromspurious magnetic fields generated by the transmitter (charger) to avoidinterference with electronics and EM related health issues.

In a variation of the above system, two charger coils (one generatingthe RF and a high Q power transfer coil) and two receiver coils (onehigh Q power transfer coil and a receive coil connected to a load) canbe used. Systems such as those shown in FIGS. 3 and 4 are often referredto as Magnetic Resonance (MR) systems due to the large gap presentbetween the coils during operation. As described previously however, MRis usually referred to inductive power transfer when the coils arefarther apart or of dissimilar size (low coupling coefficient). In atypical MR system developed for EV charging, a large portion of themagnetic field generated between the coils can be leaked to surroundingsat coil to coil vertical gap of 20 cm and laterally offset coils. Thislarge amount of radiation in such systems resulting in largeelectromagnetic interference with adjacent electrical and electronicssystems, health concerns and low efficiency is a significant challengefacing wireless power charging of EVs. Some of the drawbacks with thesesystems include:

1. High lateral (x and y) sensitivity: The amount of power transfer andefficiency of existing Wireless Charging systems is highly positiondependent. For charger and receiver coil sizes of 40-50 cm diameter, thealignment accuracy can be a fraction of this size (.+−0.10 cm) requiringprecise positioning of the vehicle with respect to the charger and/orcomplex methods for alerting and guiding the driver for precisepositioning of the two parts. Three methods of alignment are underconsideration by an SAE J2954 standard under consideration for thisapplication:

a. Triangulated RFID Positioning (using multiple RFID tags totriangulate and guide positioning).

b. Magnetic Coupling Positioning (applying a magnetic ping and finding asweet spot for alignment).

c. Combination Positioning (RFID for initial proximity detectionfollowed by magnetic coupling positioning for sweet spot alignment).

2. Receiver coil placement in the electric vehicle: The lateralsensitivity also causes difficulties in establishing a location forplacement of the receiver coil in the vehicle. Due to automobile designdifferences, it may not be always possible for the manufacturers toagree on a precise location for placement of the receiver coil in allEVs. In that case, if the charger coils are embedded in staticconditions such as parking structures or garages or in quasi-dynamic(i.e. charging while briefly stopped such as at a stop sign or trafficsignal) situations, alignment of the receiver coils and charger coilscannot be guaranteed for all EVs.

3. Lower efficiencies: In modeling and manufacture of transformers, itis known that to optimize power transfer, low reluctance paths betweenthe primary and secondary windings are essential. The systems such asshown in FIGS. 3 and 4 do not provide a low reluctance path for thereturn of the magnetic flux lines between the charger and receiver andthus do not provide for a high efficiency system. These additionallosses can be high and can lead to power loss, heating, and EMFaffecting nearby devices, vehicles and passengers.

4. High spurious Electromagnetic Field (EMF) emission: Magnetic Resonantsystems suffer from large EMF emission problems. Even in low powersystems designed for 5 W, experimental and modeling work demonstratethat EMF emissions may exceed the Federal Communication Commission (FCC)and safety limits for human exposure by 30-40 dB. The exposure levels atseveral kW of transmitted power can be proportionally greater, leadingto unsafe operation. In EV trials of Magnetic Resonant wirelesscharging, high amounts of interference with automotive electronicssystems have been observed, causing malfunction and lock out of ignitionand door lock systems.

The above approach generally requires a driver to guide the vehicle toan optimum alignment position with a high degree of accuracy. Inaccordance with an embodiment, a system with large alignment toleranceis highly desirable.

In accordance with an embodiment, the system described here addressesthe drawbacks with respect to alternative systems for charging of anymobile system such as electric vehicles, buses, trains, robot ortransport systems, etc. In accordance with an embodiment, the systemenables higher 3-dimensional positioning flexibility, higher powertransfer efficiency, and lower unwanted electromagnetic (EM) emissionsby incorporating several improvements. These improvements in positioningalso allow a vehicle, robot or system to be charged while in motion.

In accordance with an embodiment using field guiding (FG), the returnpaths of the AC magnetic flux behind (sides opposite to the gap betweenthe coils) the charger and receiver coils are designed and guided toprovide a low reluctance path by appropriate design of magnetic layersbelow the charger coil(s) and above the receiver coil(s). Magneticlayers are extended beyond the charger and receiver coil areas to allowfor overlap of the magnetic layers and to allow the returning flux linesto close on themselves, as shown 150 in FIG. 5. Advantages of thismethod include lower loss, higher efficiencies and lower EMF emissions.Modeling and tests on systems with such flux guides have shown that sucha system can result in significantly higher system efficiency.

In accordance with an embodiment to further facilitate coupling of themagnetic field to the receiver coil(s), the receiver system mayincorporate an additional magnetic material in the center of thereceiver coil such as shown in FIG. 5. This component may comprise thesame or different material that is used behind the receiver coil and itsproperties may be optimized for its particular use. As an example, solidor flexible Ferrite material with a desirable permeability can beincorporated. The core may only have the thickness of the PCB or Litzwire receiver coil and as such may have thickness of several tenths ofmillimeter and be of minimal thickness and weight. However incorporationof this core to the receiver coil may affect the receiver coilinductance, and considerably affect the efficiency and power handlingcapability of the system.

FIG. 5 shows the incorporation of a magnetic core to the central area ofa Flux Guide system. In accordance with other embodiments, the magneticcore can be added to the MR, MC, and MA receiver systems describedearlier to similarly enhance their performance.

In accordance with an embodiment shown 160 in FIG. 6, by using a crossedcharger and receiver coil and shield geometry, overlap of some portionof the charger and receiver coil over a wide range of x (along width ofthe vehicle) and y (along the length of the vehicle) can be assuredallowing large positioning tolerance in the design. The dimensions ofthe coils can be adjusted according to requirements of positioningtolerance providing a very flexible design platform. This design alsoprovides a low reluctance return path thus providing high efficiency andlow unwanted EM emissions.

Additional aspects of various embodiments are described in U.S.Provisional Patent Application No. 61/613,792, filed Mar. 21, 2012,which is herein incorporated by reference.

In accordance with an embodiment, a method is described for containingthe EM emission from the charger only to the location where the receiver(attached to the bottom of the vehicle or other system) is in alignment.This is an important factor because otherwise excessive chargeremissions may be emitted from other locations of the charger coil intothe vehicle and surrounding areas reducing the system efficiency andincreasing unwanted EM emissions. In accordance with an embodiment, thetechnology described herein takes advantage of the nonlinear behavior ofmagnetic ferrite materials for achieving this. To achieve the desiredlocalization, the charger coil is covered by an appropriate magneticlayer that shields the majority of the charger emissions. By designingthe system appropriately, a small amount of the evanescent magneticfield in the surrounding area of the charger coil and the shield canreach the receiver. In the linear regime of operation, the magneticfield strength H is related to the magnetic flux density B through thepermeability of the material μ

B=μH+M

In the above equation, M is the magnetization of a material. It must benoted that B, H, and M are vectors and μ is a scalar in isotropicmaterials and a tensor in anisotropic ones. In anisotropic materials, itis therefore possible to affect the magnetic flux in one direction witha magnetic field applied in another direction. The permeability ofFerromagnetic materials is the slope of the curves 170 shown in FIG. 7and is not constant, but depends on H. In Ferromagnetic or Ferritematerials as shown in FIG. 7, the permeability increases with H to amaximum, then as it approaches saturation it decreases by orders ofmagnitude toward one, the value of permeability in vacuum or air.Generally, the mechanism for this nonlinearity or saturation is asfollows: for a magnetic material including domains, with increasingexternal magnetic field, the domains align with the direction of thefield (for an isotropic material) and create a large magnetic fluxdensity proportional to the permeability times the external magneticfield. As these domains continue to align, beyond a certain value ofmagnetic field, the domains are all practically aligned and no furtherincrease in alignment is possible reducing the permeability of thematerial by orders of magnitude closer to values in vacuum or air.

Different materials have different saturation levels. For example, highpermeability iron alloys used in transformers reach magnetic saturationat 1.6-2.2 Tesla (T), whereas ferromagnets saturate at 0.2-0.5 T. One ofthe Metglass amorphous alloys saturates at 1.25 T. The magnetic field(H) required to reach saturation can vary from 100 A/m or lower to1000's of A/m. Many materials that are typically used in transformercores include materials described above, soft iron, silicon steel,laminated materials (to reduce eddy currents), silicon alloyedmaterials, Carbonyl iron, Ferrites, Vitreous metals, alloys of Ni, Mn,Zn, Fe, Co, Gd, and Dy, nano materials, and many other materials insolid or flexible polymer or other matrix that are used in transformers,shielding, or power transfer applications. Some of these materials maybe appropriate for applications in various embodiments described herein.

FIG. 8 shows the hysteresis curve 180 for a hard ferromagnetic materialsuch as steel. As the magnetic field is increased, the magnetic fluxsaturates at some point, therefore no longer following the linearrelation above. If the field is then reduced and removed, in some media,some value of B called the remanence (Br) remains, giving rise to amagnetized behavior. By applying an opposite field, the curve can befollowed to a region where B is reduced to zero. The level of H at thispoint is called the coercivity of the material.

Many magnetic shield layers comprise a soft magnetic material made ofhigh permeability ferromagnets or metal alloys such as large crystallinegrain structure Permalloy and Mu-metal, or with nanocrystalline grainstructure Ferromagnetic metal coatings. These materials do not block themagnetic field, as with electric shielding, but instead draw the fieldinto themselves, providing a path for the magnetic field lines aroundthe shielded volume. The effectiveness of this type of shieldingdecreases with the decrease of material's permeability, which generallydrops off at both very low magnetic field strengths, and also at highfield strengths where the material becomes saturated as described above.The permeability of a material is in general a complex number:

μ=μ′+jμ″

where μ′ and μ″ are the real and imaginary parts of the permeabilityproviding the storage and loss component of the permeabilityrespectively. FIG. 9 shows the real (top curve) and imaginary (lowercurve) part of the permeability 190 of a ferromagnetic material as afunction of applied Electromagnetic frequency.

FIG. 10 shows the magnetization curves 200 of a high permeability (realpermeability of about 3300) proprietary soft magnetic ferrite materialat 25° C. and 100° C. temperature. Increase of temperature results in areduction in the Saturation Flux density. But at either temperature,saturation of the flux density B with increasing H is clearly observed.A distinct reduction in the slope of B-H curve (i.e. materialpermeability) is observed at around 100 A/m and the reduction of thepermeability increases with H increase until the material permeabilityapproaches 1 at several hundred A/m. This particular material is MnZnbased and retains high permeability at up to 1 MHz of applied fieldfrequency but loses its permeability at higher frequencies. Materialsfor operation at other frequency ranges also exist. In general, MnZnbased materials may be used at lower frequency range while NiZn basedmaterials are used at higher frequencies up to several hundred MHz. Itis possible with appropriate material engineering and composition tooptimize material parameters to obtain the desired real and imaginarypermeabilities at any operating frequency and to also achieve thesaturation magnetic field and behavior desired.

The permeability of Ferromagnetic materials is the slope of the curvesshown in FIG. 10 and is not constant, but depends on H. In Ferromagneticor Ferrite materials, the permeability increases with H to a maximum,then as it approaches saturation it decreases by orders of magnitudetoward one, the value of permeability in vacuum or air.

In accordance with an embodiment 210 shown in FIG. 11, the field guidedsystem of FIG. 5 can be modified by adding a magnetic switching layer tothe charger at a location above the charger coil. The coils are used ina system as shown in FIG. 2 which shows a high level view of the maincomponents of a wireless charger system, wherein the charger andreceiver coils L1 and L2 can be operated in resonance with correspondingcapacitors C1 and C2 such that the LC circuit in the charger andreceiver are both in resonance at the same frequency. Operating thecharger and receiver at this resonance, the magnetic field in thelocation just in between the charger and receiver coils can build up tomuch higher levels than the surrounding area due to the Q factor of theresonance of the coils and their respective capacitors and saturate themagnetic layer in this area creating an open magnetic aperture allowingtransmission of the magnetic flux and power. This system combines fluxguiding (FG) with a Magnetic Coupling (MC) technique, to provide furtherreduction of emissions from the charger coil at areas where the receiveris not present, and may be advantageous in some applications.

U.S. Provisional Patent Application No. 61/613,792, filed Mar. 21, 2012;U.S. patent application Ser. No. 13/352,096, filed Jan. 17, 2012(published as U.S. Publication No. 20120235636); and PCT Application No.PCT/US2012/021729, filed Jan. 18, 2012; each of which applications areherein incorporated by reference, describe in further detail variousembodiments of this technology and approach.

Tests of mobile wireless charger systems incorporating abovetechnologies have shown that the efficiency of the system can beimproved by up to 10% compared to fixed position power transfer betweentwo coils when field guiding (FG) and/or flux guiding and MC techniquesdescribed above are used. In addition, the EMF emission is reduced by40-50 dB over conventional magnetic resonance systems resulting insystems meeting or exceeding regulatory guidelines. In prototypes andsystems developed for mobile device charging incorporating thistechnology, a ratio of 6 or higher y axis tolerance compared to theheight of a receiver coil can be obtained with minimal to low loss ofefficiencies. For an EV application and a receiver coil of 0.5 m×0.5 mdimensions and a charger coil of 0.5 m×2 m dimensions positioningtolerance of as much as ±0.5 m along the width of the vehicle and ±1 malong the length of the vehicle may be expected.

An important aspect of any practical wireless charging systemdevelopment and implementation is the susceptibility of the system tonearby metallic parts. In a conventional magnetic resonant (MR) system,any metal sheet or part placed in between or near the coils during powertransfer will absorb electromagnetic radiation during power transfercausing high levels of dangerous heating due to the eddy currents set upby a pulsing magnetic field in a metal (same operating principle as aninductive cooker) especially at frequencies>100 kHz and for ferrousmetals. This could result in unsafe operation or safety issues if ametal can or a metal foil or container, keys, coins, etc. isaccidentally placed near this area.

In accordance with an embodiment, the build-up of the magnetic fieldbetween the coils at a particular location allows opening up themagnetic aperture in that area. Therefore when a metal part is placed inthat area, the magnetic field cannot build up and no power transferoccurs. This behavior results in an automatic method for eliminating hotspots due to presence of metal in between the coils and eliminating avery serious and difficult problem in practical use of wireless chargingin EV charging.

In accordance with an embodiment, this behavior is confirmed in wirelesscharging systems developed with Flux Guide and Magnetic Coupling(saturation) that have safer operation in the presence of metallic partsor materials. Advantages of the above approach over conventional MRsystems include:

1. Higher system power transfer efficiencies over a range of x and yalignments resulting from optimized magnetic coupling and return fluxpath over a range of positions.

2. Larger lateral (x and y dimension) position insensitivity and z gapheight resulting from the unique crossed coil structure and flux returngeometry.

3. Lower unwanted EM emissions resulting in lower ElectromagneticCompatibility issues and human health concerns.

4. Low metal susceptibility.

In accordance with an embodiment, the communication protocol can be onethat is specific for the application. For example, in accordance with anembodiment, in the case of charging for electric vehicles, as shown 220in FIG. 12, the communication between the charger and the receiver mayfollow a number of protocols including automotive specific procedures orprotocols. For example, the main communication and control protocol tobe used in the system may be 1-way or 2-way Dedicated Short RangeCommunications (DSRC) at 5.9 GHz. The system can be initially activatedthrough radio-frequency identification (RFID) or NFC or otherrecognition or ID systems between the charger and the receiver. Onceapproach of a vehicle or system or robot or other system to be chargerhas been detected and verified through such a system, a low power ping(short power application) from the charger can be initiated to energizeand power the receiver circuit. Once the receiver is powered and DSRC orother communication and control protocol is established and verified,full charging and power transfer is initiated. The receiver system willnot apply the power to the car charging system until the received poweris stabilized and various safety and interlock tests have been verified.These can include verification of efficiency, temperature, and foreignobject detection tests.

In accordance with an embodiment, in the case that communication isprovided through the power transfer coil, one method for thecommunication is to modulate a load in the receiver to affect thevoltage in the receiver coil and therefore create a modulation in thecharger coil parameters that can be detected through monitoring of itsvoltage or current. Other methods can include frequency modulation bycombining the received frequency with a local oscillator signal orinductive, capacitive, or resistive modulation of the output of thereceiver coil.

In accordance with an embodiment, the communicated information can bethe output voltage, current, power, device or battery status, validationID for receiver, end of charge or various charge status information,receiver battery, device, or coil temperature, and/or user data such asinformation about the user, verification of ability to account andcharge a customer for a charging/power service, etc or provide true datacommunication that can be used to perform system or firmware updates,diagnostics, etc. The communication can also be a pattern or signal orchange in the circuit conditions that are transmitted or occurs tosimply notify the presence of the receiver nearby.

In accordance with an embodiment shown in FIG. 12, the data communicatedcan be any one or more of the information detailed herein, or thedifference between these values and the desired value or simple commandsto increase or decrease power or simply one or more signals that confirmpresence of a receiver or a combination of the above. In addition, thereceiver can include other elements such as a DC to DC converter orregulator such as a switching, buck, boost, buck/boost, or linearregulator. The receiver can also include a switch between the DC outputof the receiver coil and the rectification and smoothing stage and itsoutput or the output of the regulator stage to a device or battery or adevice or system or EV or robot attachment and in cases where thereceiver is used to charge a battery or device, the receiver may alsoinclude a regulator, battery charge management IC or circuitry and/orbattery protection circuit and associated electronics, etc. The receivermay also include variable or switchable reactive components (capacitorsand/or inductors) that allow the receiver to change its resonantcondition to affect the amount of power delivered to the device, load orbattery. The receiver and/or charger and/or their coils can also includeelements such as thermistors, magnetic shields or magnetic cores,magnetic sensors, and input voltage filters, etc. for safety and/oremission compliance reasons.

Safety standards with respect to Human exposure to Electromagneticradiation exist. For example, the International Commission onNon-Ionizing Radiation Protection (ICNIRP) has developed severalguidelines covering the acceptable limits of Electromagnetic Fields(EMF) up to 300 GHz (1998) and in the range of 100 kHz-300 GHz (2009).These considerations must be taken into account in design of anypractical wireless charging system and appropriate coil and magneticssystems incorporated.

In accordance with an embodiment, the receiver may also be combined withother communication or storage functions such as NFC, WiFi, Bluetooth,etc. In addition, the charger and or receiver can include means toprovide more precise alignment between the charger and receiver coils orantennas. These can include visual, physical, or magnetic means toassist the user in alignment of parts. To implement more positioningfreedom of the receiver on the charger, the size of the coils can alsobe mismatched. For example, the charger can comprise a larger coil sizeand the receiver a smaller one or vice versa, so that the coils do nothave to be precisely aligned for power transfer.

In accordance with an embodiment, in simpler architectures, there may beminimal or no communication between the charger and receiver. Forexample, a charger can be designed to be in a standby power transmittingstate, and any receiver in close proximity to it can receive power fromthe charger. The voltage, power, or current requirements of the deviceor battery connected to the receiver circuit can be unregulated, orregulated or controlled completely at the receiver or by the deviceattached to it. In this instance, no regulation or communication betweenthe charger and receiver may be necessary. In accordance with anembodiment, in a variation of this, the charger can be designed to be ina state where a receiver in close proximity can bring it into a state ofpower transmission. Examples of this include a resonant system whereinductive and/or capacitive components are used, so that when a receiverof appropriate design is in proximity to a charger, power is transmittedfrom the charger to a receiver; but without the presence of a receiver,minimal or no power is transmitted from the charger.

In accordance with an embodiment, in a variation of the above, thecharger can periodically be turned on to be driven with a periodicpattern (a ping process) and if a receiver in proximity begins to drawpower from it, the charger can detect power being drawn from it and stayin a transmitting state. If no power is drawn during the ping process,the charger can be turned off or placed in a stand-by or hibernationmode to conserve power and turned on and off again periodically tocontinue seeking a receiver.

In accordance with an embodiment, the power section (coil drive circuitand receiver power section) can be a resonant converter, resonant, fullbridge, half bridge, E-class, zero voltage or current switching,flyback, or any other appropriate power supply topology. For example,FIG. 2 described above shows a wireless charger system in accordancewith an embodiment, with a resonant converter geometry, wherein a pairof transistors Q1 and Q2 (such as FETs, MOSFETs, or other types ofswitch) are driven by a half-bridge driver IC and the voltage is appliedto the coil L1 through one or more capacitors shown as C1. The receiverincludes a coil and an optional capacitor (for added efficiency) shownas C2 that can be in series or in parallel with the receiver coil L2.The charger and/or receiver coils may also include impedance matchingcircuits and/or appropriate magnetic material layers behind (on the sideopposite to the coil surfaces facing each other) them to increase theirinductance and/or to shield the magnetic field leakage to surroundingarea. The charger and/or receiver may also include impedance matchingcircuits to optimize/improve power transfer between the charger andreceiver.

In many of the embodiments and figures described herein, the resonantcapacitor C2 in the receiver is shown in a series architecture. This isintended only as a representative illustration, and in accordance withother embodiments, this capacitor can be used in series or parallel withthe receiver coil. Similarly, the charger is generally shown in anarchitecture where the resonant capacitor is in series with the coil. Inaccordance with an embodiment, system architectures with the capacitorC1 is in parallel with the charger coil are also possible.

In accordance with an embodiment, such as that shown in FIG. 12, thecharger section can be powered by an AC power source such as from apower outlet or available grid power. This AC voltage can be rectifiedbefore application to the wireless charger power section. In addition,to maximize the efficiency of the system, a Power Factor Correction(PFC) system or network can also be implemented. Furthermore, thecharger can be designed such that in addition to wireless charging, itmay provide optional wired charging and communication to the system,robot or vehicle to be charged. As an example, wired charging of an EVmay follow existing connector and communication standards such as ASEJ1772 Standard.

In accordance with an embodiment, the charger also includes a circuitthat measures the current through and/or voltage across the chargercoil. In accordance with embodiments or systems whereby thecommunication occurs through the power transmission coils (similar toshown in FIG. 1), various methods for detection of the communicationsignal on the charger current or voltage are available. Thisdemodulation and detection mechanism can be, for example, an AM or FMreceiver (depending on whether amplitude or frequency modulation isemployed in the receiver modulator) similar to a radio receiver tuned tothe frequency of the communication or a heterodyne detector, etc. Inaccordance with an embodiment, once the charger MCU has received asignal through wired or wireless communication and decoded it, the MCUcan take action to provide more or less power to the charger coil. Thiscan be accomplished through known methods of adjusting the frequency,duty cycle or input voltage to the charger coil or a combination ofthese approaches. Depending on the system and the circuit used, the MCUcan directly adjust the bridge driver, or an additional circuit such asa frequency oscillator may be used to drive the bridge driver or theFETs.

In accordance with an embodiment, the microcontroller unit (MCU) in thecharger (MCU1) is responsible for understanding the communication signalfrom the detection/demodulation circuit and, depending on the algorithmused, making appropriate adjustments to the charger coil drive circuitryto achieve the desired output voltage, current or power from thereceiver output. In addition, MCU1 is responsible for processes such asperiodic start of the charger to seek a receiver at the start of charge,keeping the charger on when a receiver is found and accepted as a validreceiver, continuing to apply power and making necessary adjustments,and/or monitoring temperature or other environmental factors, providingaudio or visual indications to the user on the status of charging orpower process, etc. or terminating charging or application of power dueto end of charge or customer preference or over temperature, overcurrent, over voltage, or some other fault condition or to launch orstart another program or process.

For example, in the case of EV charging described above, when thevehicle is being charged wirelessly, communication between the wirelesspower receiver and/or the battery or its charging circuit and the EV canbe performed by one or a number of the on-board diagnostic (OBD) orother protocols such as Controller Area Network (CAN) incorporated intothe vehicle's communication system. In accordance with an embodiment,such communication can communicate with the EV and/or the battery and/orits charging circuit can provide detailed info on the battery's state ofcharge, its temperature, required current/voltage or its state ofhealth. In addition, initiation of wireless charging can be signaled tothe vehicle to provide visual and/or auditory signal to the user,disable the vehicle movement during charge, or other actions. Thesignaling to the user can also be provided remotely. For example thevehicle and/or the charger or the receiver can provide remoteinformation on progress of charging or any faults or errors to a driveror designated person who may be outside the vehicle at home, office,restaurant, etc. through a WiFi, GSM, 3G, 4G, Bluetooth, etc. network bysending real time information to a handheld or portable device orcomputer such as a phone, laptop, tablet, desktop computer, TV, etc byemail, text, phone calls, fax, custom application (app) or othercommunication mechanisms. For example a driver can be alerted that theEV battery has reached full charge or how many miles of driving can beexpected from the current state of charge in real time as the chargingprogresses. In accordance with an embodiment, the charger and/or thereceiver or the vehicle can also be programmed to contact utilityservice providers and depending on the electricity rate at any giventime or the load of the electrical network, etc., optimize the chargecommencement and/or termination time or charge rate for optimum networkload, minimum electricity cost, or other desirable performanceattributes.

In accordance with an embodiment, the charger system and/or the EV to becharged can be connected by land or wireless connections to a system forverification and billing/tolling of the electricity used during chargingin public locations such as public or office parking, hotel, restaurant,roadways, structures, etc. To identify an EV, systems such as RFID, NFC,etc. can be used and once an EV is parked or placed in the vicinity of awireless charger even while moving, it can be recognized and the EV useror responsible party can be charged or billed through a pre-registeredor such payment system for the amount of electricity used during EVcharging.

In accordance with an embodiment, as shown in FIG. 12, the communicationbetween the charger and receiver for EV charging can be implemented witha separate RF channel. An example of this channel is the Dedicated ShortRange Communication (DSRC) one way or two way communication which isused for in-vehicle or between-vehicle communication at 5.9 GHz band.Examples of its use are in toll collection, Cooperative Adaptive CruiseControl, Collision Warning, etc.

In accordance with an embodiment, to recognize arrival or proximity of avalid EV for charging or to aid in alignment within required tolerancesfor valid charging, use of RFID or NFC, Bluetooth, or other wirelessdetection between the charger and receiver/vehicle can be used toindicate approach of a valid vehicle. This can be followed by moreprecise triangulation techniques using multiple detectors to guide theEV operator to bring the EV to better alignment. For example, 2, 3 or 4detectors located in a triangular or square pattern in or on the chargerand correspondingly placed tags on the EV can be used to provide the EVoperator info on the alignment based on strength of signals. Conversely,the tags can be placed on or in the charger and the detectors can be inthe EV.

In accordance with an embodiment, once a rough or approximate alignmentis reached a wireless communication link between the charger andreceiver and the battery and its charging system can be established anddiagnostic tests performed. The charger can further then test theavailability and operation of a receiver on the EV by sending a burst ofpower (ping signal) to power the receiver system in the EV. Initiallythe receiver can then perform a thorough self-test of its operations andthe battery and its charging system, temperature, etc. before requestingthe appropriate power and commencing charging or connecting to thecharger system to provide power.

In accordance with another embodiment, an initial recognition andidentification of an approaching and aligned device can be performed byRFID or similar methods, wherein the charger may send out a burst ofpower (ping) to power the receiver, which in turn would power thereceiver communication module and initiate further identification andcommunication for power transfer. In accordance with this embodiment,the receiver is fully or almost fully powered by the charger, andtherefore a vehicle with no battery charge can also be powered since allthe power for identification, communication and control is provided bythe charger.

While the description above has described situations where a vehicle,robot, train, bus, etc. is being moved to the vicinity of a charger orpower supply to receive power during parking or a stationary chargingcondition, in accordance with another embodiment, one or severalchargers can be placed in one or more locations along the path of amobile vehicle, train other transport device or vehicle or robot suchthat, during temporary stoppage or slow down, it can receive power.Examples of such implementation can include an Electric Vehicle stoppingat a red light or traffic stop or a robot stopping at set positionsduring performance of tasks and receiving power before moving on. Insuch embodiments, sensors such as described above can signal thepresence of a receiver nearby and initiate further identification of thereceiver or receivers and transfer of power. In addition to suchquasi-static wireless charging, it may be advantageous to providecharging or power continuously during the movement of a receiver. Anexample can include a train moving along a set track and receiving powercontinuously or an embodiment where a series of continuous ordiscontinuous chargers are embedded in a road, and an Electric Vehiclecan be charged or powered while being driven on the road.

In accordance with an embodiment such as that shown 230 in FIG. 13, thecharger can be continuous or built from one or more chargers and/orcoils that each cover a set length or majority of the length of theroad, path or train track. Approach of a vehicle, train, robot, etc. issignaled in a manner similar to described above and the charging orpower application is performed while the vehicle or train, robot, etc.is in the vicinity of each segment before being disconnected when itmoves to the next segment.

To provide safe charging performance, it may be necessary during thecharging to compare the power transferred to the power received and/oravailable for charging. This can be performed by charger and/orreceiver. If these power levels indicate a large discrepancy fromexpected values and the efficiency of power transfer in the system, thismay indicate the presence of a metal or other anomaly in the systemrequiring a warning or shut down or other actions to be taken. Suchsafety interlocks can be implemented and activated by the charger,receiver or both systems.

While many of the techniques described herein improve efficiency andalignment insensitivity, decrease unwanted EM emission and performanceof the systems would improve the safety and benefits of the system, theycan be combined with such methods described above for alignment,verification and safety of the system to provide even more secureperformance or to provide additional features to the user. In anotherembodiment of the system, the charger and/or receiver, system, robot orEV to be charged may include systems for measurements of stray orspurious EM emission at one or more locations and may take action tokeep this emission to acceptable levels. The range of action to be takencan include shutdown of the system, adjustment of power to lower levels,instructing the operator or driver to move the receiver or the system,robot, or EV to be charged to a location to reduce unwanted EM emission,etc. or a combination of such actions.

An area of concern for EV charging is that during charging, smallanimals such as dogs and cats or other pets or children or humans maymove in between the coils or other high magnetic field areas and beexposed to EM emissions. Since the EM field profile is largelyimpervious to the presence of tissue, bones, etc. such presence may notbe detected by comparing the received power to expected power levels. Inaccordance with an embodiment shown in FIG. 12 and described above, toavoid charging or power transfer in the presence of such living tissue,the charger and/or receiver or the system to be charged, robot, or EVmay incorporate a proximity sensor to sense such presence. Examples ofpotential such sensors are capacitive, Doppler, resistive, laser ordiode or rangefinder, optical, thermal, photocell, radar, sonar,ultrasonic, weight etc. methods of detection that can be used. Inanother embodiment one or more visible wavelength range cameras orinfrared detectors, monitors or cameras monitor the space between thecoils and any anomalies or movement in this area is used to terminatecharging or take other actions such as to issue a warning, shut downcharging, etc.

In accordance with an embodiment, the system shown in FIG. 12 can beused with a robot or EV and/or their battery in communication that isbeing powered and/or charged. The charger and/or the system, robot or EVcan itself be connected to a Personal Area Network (PAN), Local AreaNetwork (LAN), Wide Area Network (WAN), Metropolitan Area Network (MAN),Satellite, or cellular networks (3G, 4G, GSM, Edge, etc.) or specificnavigation or other networks through wired methods, wireless methods,fiber optics, DSL, WiMAX, WiFi, dial up modem, etc. Also the host andthe mobile device can communicate through a variety of wired or wirelessmethods such as USB, Bluetooth, WiFi, WiMAX, Wireless USB, DSRC, CAN,NFC, RFID, etc. The communication and power transfer for charging and/orpowering of the system, robot or EV to be charged or powered and/or thecharger can be wired (through a wired charger and communication path orsuch) or wireless (through induction, conduction, magnetic resonancetechniques, microwave, optical, solar cells, etc.). In FIG. 12, only asubset of potential protocols and methods for connectivity andcommunication and charging/power have been shown but, in accordance withvarious embodiment, other protocols and methods, including specificprotocols for control of devices in the home and/or car or otherspecific situations, can be used.

In accordance with an embodiment, a system such as that shown in FIG. 12for example, comprises the power paths and power control signals shownin solid lines. Data lines are in dashed lines. Double dashed linesrepresent connections that can be data or charger and/or power supplysignals. The charger and/or power supply comprises a drive circuit forexciting the charger coil. This can be a field effect transistor (FET)or other transistor for generating the alternating current to drive thecoil. The regulation/communication and control section is responsiblefor controlling the frequency/pulse duration, or other characteristicsof the drive to control the transferred power or to communicate a signalor data to the receiver. In addition, the circuit can contain a sensecircuit that is used to sense the proximity of the receiver and/or as acomponent for data or signal transfer between the charger and/or powersupply and the receiver.

In accordance with an embodiment, in a general geometry such as thatshown in FIG. 12, the regulation/communication & control portion or aseparate circuit can also provide a communication channel for data toand from a charger or home or office or other device where thecharger/power supply is located or is connected to or nearby. By beingnear each other, we mean that 2 devices are within a distance such thatthey can interact through a wireless, wired, optical, or other method orprotocol within a Personal Area Network (PAN) or Local Area Network(LAN). The mobile device and/or the charger can contain additionalcommunication systems such as Bluetooth, WiFi, WiMAX, GSM, 3G, 4G,Wireless USB, Zigbee, NFC, RFID, GPS, or wired communications such asUSB, Ethernet, DSL, Modem, Fiber optics, Optical, HDMI, Power LineCommunication (PLC), or other protocols for communications and controlbetween devices and internet or systems such as in the house, car, etc.The charging and/or power for the system, robot or EV can be throughinduction, conduction, resonant magnetic power transfer, optical power,etc. and/or traditional wired technologies.

In accordance with various embodiments, data can be the control andcommunication signals necessary for the charging or power transferprocess but it may also involve communication, information or file orsignals that are exchanged that are not necessarily directly involved inthe charging/power supply operation. Examples of information beingexchanged between components for charging/power supply function isreceiver voltage, current, voltage, any fault condition(over-temperature, over-voltage), end of charge or other charger signals(CS). Examples of application data (AD) can be name, address, phonenumber, or calendar information, verification or ID or billinginformation or application/update files. In addition, data can beinformation related to amount of charge in a battery, presence of amobile system, robot or EV on a charger, type of device or battery beingcharged, information about the user and their preferences, location orstatus of the device or battery being charged, etc. In FIG. 12, theapplication data (AD) lines have been shown in dotted line while thesolid lines represent connections for charging function. Someconnections such as the one from the sense circuit to the regulation,communication and control can be for application data or charging signaldepending on whether any data exchange is implemented or the sensecircuit is strictly used for charger and/or power supply (CS) functions.Similarly, for example, the connection from the device or system orrobot or EV being charged to the regulation, communication, and controlcircuit in the receiver can be either for data (AD) or charger and/orpower supply signal (CS). These signals are shown with double dottedlines in FIG. 12. The breakdown between CS and AD shown is as an exampleand many other situations where the signals may be interpreted asbelonging to either group or both may occur.

In accordance with an embodiment, such as that shown in FIG. 12, ageneral schematic which can include bi-directional data and CS transferis shown. However, the flow of information can be uni-directional aswell. In this case, for example, if the CS and data is from receiver tocharger and/or power supply, only a sense circuit in the charger and/orpower supply may be implemented. In the block diagram shown in FIG. 12,the data from the charger and/or power supply to the receiver may alsobe transferred by low or high frequency modulation of the amplitude ofthe power signal (the drive signal for power transfer) or frequencymodulation and filtering or synching in the receiver. These techniquesare often used in communication circuits and can be applied herein, inaccordance with an embodiment.

In accordance with an embodiment, AD or CS information can betransferred from receiver to charger and/or power supply by techniquessuch as modulating the load impedance of the receiver, or othertechniques, as described for example in U.S. patent application titled“SYSTEM AND METHOD FOR INDUCTIVE CHARGING OF PORTABLE DEVICES”,application Ser. No. 12/116,876, filed May 7, 2008, (published as U.S.Patent Publication No. 20090096413), which is incorporated by referenceherein. In this way, any AD or CS in the receiver appears as a change inthe load of the charger and/or power supply output and can be sensed bythe charger and/or power supply sense circuitry. The data exchangedbetween the charger and/or power supply and the receiver can beexchanged in analog or digital format and many options for this exchangeexist.

In accordance with other embodiments, it is possible to have the dataand/or charge signal data transferred through another mechanism separatefrom the power signal. In accordance with an embodiment, such as thatshown in FIG. 12, a wireless channel for data and CS is shown where thewireless channel can be a dedicated special channel between the chargerand/or power supply and the receiver or can be based on an existingprotocol such as Bluetooth, WiFi, WiMAX, Wireless USB, Zigbee, NFC,DSRC, CAN, etc. or a custom or proprietary protocol.

It can be readily appreciated that in the above descriptions manygeometries and systems have been described. In practice, one or severalof these systems can be used in combination in a charger and/orreceivers to provide the desired performance and benefits.

The above description and embodiments are not intended to be exhaustive,and are instead intended to only show some examples of the rich andvaried products and technologies that can be envisioned and realized byvarious embodiments of the invention. It will be evident to personsskilled in the art that these and other embodiments can be combined toproduce combinations of above techniques, to provide useful effects andproducts.

Some aspects of the present invention can be conveniently implementedusing a conventional general purpose or a specialized digital computer,microprocessor, or electronic circuitry programmed according to theteachings of the present disclosure. Appropriate software coding canreadily be prepared by skilled programmers and circuit designers basedon the teachings of the present disclosure, as will be apparent to thoseskilled in the art.

In some embodiments, the present invention includes a computer programproduct which is a storage medium (media) having instructions storedthereon/in which can be used to program a computer to perform any of theprocesses of the present invention. The storage medium can include, butis not limited to, any type of disk including floppy disks, opticaldiscs, DVD, CD-ROMs, microdrive, and magneto-optical disks, ROMs, RAMs,EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or opticalcards, nanosystems (including molecular memory ICs), or any type ofmedia or device suitable for storing instructions and/or data.

The foregoing description of the present invention has been provided forthe purposes of illustration and description. It is not intended to beexhaustive or to limit the invention to the precise forms disclosed.Many modifications and variations will be apparent to the practitionerskilled in the art. The embodiments were chosen and described in orderto best explain the principles of the invention and its practicalapplication, thereby enabling others skilled in the art to understandthe invention for various embodiments and with various modificationsthat are suited to the particular use contemplated. It is intended thatthe scope of the invention be defined by the following claims and theirequivalence.

What is claimed is:
 1. A system for charging of one or more devicesincluding robots, vehicles, or batteries, the system comprising: awireless charger that comprises a charger coil and an optional wiredcharger, for charging one or more devices, robots, vehicles, orbatteries, the wireless charger and the optional wired charger usingrespectively wireless and wired means of communication with the devicesto initial and control a charging process, wherein the wireless and theoptional wired charger and/or the device can communicate with a localarea, wide area, cellular, satellite, fiber, DSL or other wireless orwired network, to exchange information or update remotely regarding thecharging of the one or more devices, the one or more devices themselvesor the user.
 2. The system of claim 1, wherein-an electromagneticemission from the charger coil is generally contained to a locationabove or near the charger coil.
 3. The system of claim 1, whereinwireless communication between the wireless charger and the devices usesNear Field Communication, Bluetooth, WiFi, wireless USB, Felica, Zigbee,Wireless Gigabit, DSRC, RFID, WPC, or other custom communicationtechnology.
 4. The system of claim 1, wherein the wireless chargerperforms transferring power to the one or more devices being charged ata variety of positions by the charger coil.
 5. The system of claim 4,wherein the system performs transferring power to allow charging of amoving device, including use of one or more charger coils along a lengthupon which the moving device to be powered or to be charged can move. 6.The system of claim 1, wherein the devices comprising one or more of amobile, electronic, electric, lighting, battery, power tool, drone,kitchen, military, medical, industrial tools or other device.
 7. Thesystem of claim 1, wherein the devices comprising one or more electricvehicle, robot, train, bus, truck, electric bicycle, motorcycle, Segwaytype of device and/or other electric vehicles or other moving equipment.8. The system of claim 1, wherein a communication between the chargerand the device can follow one or a number of protocols, including in thecase of an electric vehicle including a wireless charging specific orautomotive-specific procedures or protocols including DSRC.
 9. Thesystem of claim 1, wherein approaching a device, including a vehicle orsystem or robot to be charged, has been detected and verified through acommunication such as RFID, Bluetooth, WiFi, Wireless USB, NFC, Felica,Zigbee, Wireless Gigabit (WiGig), WPC, A4WP, DSRC, or a ping or othercommunication is communicated from the charger coil to energize andpower a wireless receiver circuit in the device.
 10. The system of claim1, wherein the charger and the device can communicate informationincluding Charger Signal regarding one or more output voltage, current,power, device or battery status, validation ID for a device, end ofcharge or various charge status information, and/or Application Data oruser data comprising information about a user, verification of abilityto account and charge a customer for a charging/power service, or otherdata that can be used to perform system or firmware updates,diagnostics, billing or other tasks.
 11. The system of claim 1, whereininitiation of charging can be signaled to a device included in a vehicleby providing a visual signal and/or an auditory signal to a user therebydisabling the device or vehicle movement during charge, or otheractions.
 12. The system of claim 1, wherein initiation of charging ofthe device included in a vehicle or the vehicle itself can includebilling/tolling of the electricity used during charging in publiclocations including public or office parking garage/lots, hotel,restaurant, roadway or other structures.
 13. The system of claim 1wherein the charger, a device or a vehicle communicates with an owner ofthe vehicle or a designated person by text, email, telephone message,custom application or other means of communication about the state ofcharging of the device or the vehicle, error conditions or otherimportant information.
 14. The system of claim 1, wherein the charger,device, or vehicle being charged can also be programmed to contactutility service providers and optimize a charge commencement time and/ora termination time or a charge rate for an optimum network load, aminimum electricity cost or other desirable performance attributes. 15.The system of claim 1, wherein once a rough or approximate alignment isreached between the charger and the one or more devices a wirelesscommunication link between the charger and the one or more devices canbe established and diagnostic tests, verifications or other actionsperformed.
 16. The system of claim 1, wherein a proximity sensorincluding a capacitive, resistive, laser or diode or rangefinder,optical, thermal, photocell, radar, sonar, ultrasonic, weight or camerasor infrared sensors or other method of detection can be used todetermine a presence of a live animal or a person in a region of highmagnetic field close to the charger coil or between the charger coil andthe one or more devices and take an appropriate action.
 17. A method forwireless and/or optionally wired charging of one or more devicesincluding robots, vehicles or batteries, the method comprising the stepsof: providing a charger including a charger coil and an optional wiredcharger, for charging robots, vehicles, or batteries, the wirelesscharger and the optional wired charger using respectively wireless andwired means of communication with the devices to initiate and control acharging process, wherein the wireless and the optional wired chargerand/or the device can communicate with a local area, wide area,cellular, satellite, fiber, DSL or other wireless or wired network, toexchange information or update remotely regarding the charging of theone or more devices, the one or more devices themselves or the user.